Occasional Heart Palpitations

I am 41 years old, and over the pase several months have been experiencing palpitations. It only lasts a second or two, and maybe 2 - 3 times a week. Its usually when Im at rest. They are not followed by any other distressing symptoms. They make me uneasy afterward...like Im always waiting for something terrible to follow. Should I be concerned? Are they too infrequent to consider a problem?